Proteolytic cleavage of complement factor C4

Stable Identifier
R-GGA-2132233
Type
Reaction [omitted]
Species
Gallus gallus
Compartment
extracellular region, plasma membrane
ReviewStatus
5/5
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Proteolytic cleavage of complement factor C4
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C4 is cleaved by activated protease C1s in the classical pathway or MASPs in the lectin-mediated pathway producing two fragments C4a and C4b. The larger fragment C4b binds covalently to the target surface due to a highly reactive thioester bond which becomes exposed upon cleavage. Chicken C4 shares 37% amino acid sequence identity with its human counterpart. Correlation between chicken MBL concentration and C4 deposition was observed in chicken sera [Norup LR and Juul-Madsen HR 2007].

The exact cleavage site in chicken C4 is unknown.

Literature References
PubMed ID Title Journal Year
17954581 An assay for measuring the mannan-binding lectin pathway of complement activation in chickens

Juul-Madsen, HR, Norup, LR

Poult Sci 2007
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Catalyst Activity

serine-type endopeptidase activity of C4:factor B activator [plasma membrane]

Physical Entity
C4:factor B activator [plasma membrane] (Gallus gallus)
Activity
serine-type endopeptidase activity (GO:0004252)
Authored
Shamovsky, V  (2012-12-20)
Reviewed
D'Eustachio, P  (2012-11-07)
Jupe, S  (2013-01-31)
Created
Shamovsky, V  (2012-02-21)
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